nC2H4Br2= 0.1 (mol)

C2H4 + Br2 --> C2H4Br2

nC2H4= 0.1 (mol)

VC2H4= 2.24l

VCH4= 4-2.24=1.76l

%CH4= 44%

%C2H4= 56%

a) \(n_{C_2H_4Br_2}=\dfrac{18,8}{188}=0,1\left(mol\right)\)

PTHH: C₂H₄ + Br₂ --> C₂H₄Br₂

            0,1<----0,1<---0,1

=> \(m_{Br_2}=0,1.160=16\left(g\right)\)

b)

\(\%V_{C_2H_4}=\dfrac{0,1.22,4}{4}.100\%=56\%\)

=> \(\%V_{CH_4}=100\%-56\%=44\%\)

c) \(n_{CH_4}=\dfrac{4.44\%}{22,4}=\dfrac{11}{140}\left(mol\right)\)

PTHH: CH₄ + 2O₂ --t^o--> CO₂ + 2H₂O

          \(\dfrac{11}{140}\)-->\(\dfrac{11}{70}\)

            C₂H₄ + 3O₂ --t^o--> 2CO₂ + 2H₂O

           0,1---->0,3

=> \(V_{O_2}=\left(\dfrac{11}{70}+0,3\right).22,4=10,24\left(l\right)\)

=> V_kk = 10,24.5 = 51,2 (l)

Bài 14 : 

Vì metan không tác dụng với Brom nên : 

\(n_{C2H4Br2}=\dfrac{4,7}{188}=0,025\left(mol\right)\)

a) Pt : \(C_2H_4+Br_2\rightarrow C_2H_4Br_{2|}\)

              1          1                1

            0,025                    0,025

b) \(n_{C2H4}=\dfrac{0,025.1}{1}=0,025\left(mol\right)\)

\(V_{C2H4\left(dktc\right)}=0,025.22,4=0,56\left(l\right)\)

\(V_{CH4\left(dktc\right)}=1,4-0,56=0,84\left(l\right)\)

⁰/₀V_CH4 = \(\dfrac{0,84.100}{1,4}=60\)⁰/₀

⁰/₀V_C2H4 = \(\dfrac{0,56.100}{1,4}=40\)⁰/₀

 Chúc bạn học tốt

\(n_{C_2H_4Br_2}=\dfrac{9,4}{188}=0,05mol\)

\(n_{hh}=\dfrac{5,6}{22,4}=0,25mol\)

\(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)

0,05       0,05         0,05           ( mol )

\(m_{Br_2}=0,05.160=8g\)

\(\left\{{}\begin{matrix}\%V_{C_2H_4}=\dfrac{0,05}{0,25}.100=20\%\\\%V_{CH_4}=100\%-20\%=80\%\end{matrix}\right.\)

a) PTHH: \(C_2H_2+2Br_2\rightarrow C_2H_2Br_4\)

b) Ta có: \(\%V_{CH_4}=\dfrac{3,36}{8,96}=37,5\%\) \(\Rightarrow\%V_{C_2H_2}=62,5\%\)

c) Theo PTHH: \(n_{Br_2}=2n_{C_2H_2}=2\cdot\dfrac{8,96-3,36}{22,4}=0,5\left(mol\right)\) \(\Rightarrow m_{Br_2}=0,5\cdot160=80\left(g\right)\) 

1. \(n_{Br_2}=0,4.0,5=0,2\left(mol\right)\)

PT: \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)

Theo PT: \(n_{C_2H_4}=n_{Br_2}=0,2\left(mol\right)\Rightarrow V_{C_2H_4}=0,2.22,4=4,48\left(l\right)\)

2. \(n_{C_2H_4Br_2}=\dfrac{9,4}{188}=0,05\left(mol\right)\)

PT: \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)

Theo PT: \(n_{C_2H_4}=n_{C_2H_4Br_2}=0,05\left(mol\right)\)

\(\Rightarrow\%V_{C_2H_4}=\dfrac{0,05.22,4}{1,4}.100\%=80\%\)

\(\Rightarrow\%V_{CH_4}=100-80=20\%\)

Đáp án A